Ontology of Biological Attributes entry OBA_2053188 (DRG2/SEMA4D protein level ratio in blood) can be described as follows. A compound attribute that is the ratio of amount of developmentally-regulated GTP-binding protein 2 (human) in blood to amount of semaphorin-4D (human) in blood. Also known as: the ratio of amount of developmentally-regulated GTP-binding protein 2 (human) in blood to amount of semaphorin-4D (human) in blood.